Initial commit

Signed-off-by: Thomas Klaehn <thomas.klaehn@perinet.io>

internal/config/config.go

@@ -0,0 +1,123 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/spf13/viper"
+)
+
+// Config holds all configuration for the Zwift monitor service
+type Config struct {
+	// Authentication
+	Username string `mapstructure:"username"`
+	Password string `mapstructure:"password"`
+
+	// Storage
+	OutputDir      string `mapstructure:"output_dir"`
+	StateFile      string `mapstructure:"state_file"`
+	TokenCachePath string `mapstructure:"token_cache"`
+
+	// Monitoring
+	PollInterval time.Duration `mapstructure:"poll_interval"`
+
+	// API Configuration
+	RateLimit  int `mapstructure:"rate_limit"`
+	MaxRetries int `mapstructure:"max_retries"`
+
+	// Logging
+	LogLevel string `mapstructure:"log_level"`
+	LogFile  string `mapstructure:"log_file"`
+}
+
+// Load loads configuration from environment variables and optional config file
+func Load() (*Config, error) {
+	v := viper.New()
+
+	// Set defaults
+	v.SetDefault("output_dir", "/data/activities")
+	v.SetDefault("state_file", "/data/zwift-state.json")
+	v.SetDefault("token_cache", "/data/.zwift-token.json")
+	v.SetDefault("poll_interval", "5m")
+	v.SetDefault("rate_limit", 5)
+	v.SetDefault("max_retries", 3)
+	v.SetDefault("log_level", "info")
+	v.SetDefault("log_file", "")
+
+	// Bind environment variables
+	v.SetEnvPrefix("ZWIFT")
+	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
+	v.AutomaticEnv()
+
+	// Try to load config file if it exists
+	configPaths := []string{
+		"config.yaml",
+		"/app/config.yaml",
+		filepath.Join(os.Getenv("HOME"), ".zwift-monitor.yaml"),
+	}
+
+	for _, path := range configPaths {
+		if _, err := os.Stat(path); err == nil {
+			v.SetConfigFile(path)
+			if err := v.ReadInConfig(); err != nil {
+				return nil, fmt.Errorf("failed to read config file %s: %w", path, err)
+			}
+			break
+		}
+	}
+
+	var cfg Config
+	if err := v.Unmarshal(&cfg); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal config: %w", err)
+	}
+
+	// Validate required fields
+	if err := cfg.Validate(); err != nil {
+		return nil, err
+	}
+
+	// Expand paths (handle ~)
+	cfg.OutputDir = expandPath(cfg.OutputDir)
+	cfg.StateFile = expandPath(cfg.StateFile)
+	cfg.TokenCachePath = expandPath(cfg.TokenCachePath)
+	if cfg.LogFile != "" {
+		cfg.LogFile = expandPath(cfg.LogFile)
+	}
+
+	return &cfg, nil
+}
+
+// Validate checks if required configuration is present
+func (c *Config) Validate() error {
+	if c.Username == "" {
+		return fmt.Errorf("username is required (set ZWIFT_USERNAME environment variable)")
+	}
+	if c.Password == "" {
+		return fmt.Errorf("password is required (set ZWIFT_PASSWORD environment variable)")
+	}
+	if c.PollInterval < time.Minute {
+		return fmt.Errorf("poll_interval must be at least 1 minute")
+	}
+	if c.RateLimit < 1 {
+		return fmt.Errorf("rate_limit must be at least 1")
+	}
+	if c.MaxRetries < 1 {
+		return fmt.Errorf("max_retries must be at least 1")
+	}
+	return nil
+}
+
+// expandPath expands ~ to home directory
+func expandPath(path string) string {
+	if strings.HasPrefix(path, "~") {
+		home, err := os.UserHomeDir()
+		if err != nil {
+			return path
+		}
+		return filepath.Join(home, path[1:])
+	}
+	return path
+}